1. Origin of the Invention
The invention described herein was made in the performance of work under a NASA contract, and is subject to the provisions of Public Law 96-517 (35 USC 202) in which the Contractor has elected to retain title.
2. Field of the Invention
This invention relates to hand-held controllers and, more particularly, to a hand-held controller for robot end effectors, which controller provides force and position feedback to the operator.
2. Background of the Invention
Joystick, pistol-grip and other type hand-held controllers are well known. The controllers move an end effector in a direction that corresponds to the pivoted direction that the controller is moved. To add "feel" for the user, it is known to add resistance of various types to the controller.
A known feel-creating means for a joystick control is described in U.S. Pat. No. 3,771,037 to Bailey Jr., wherein a resilient bias means 24 is depicted in FIGS. 2, 3 and 6 and is described at column 4 lines 28 through 50. Other joystick or pistol-grip controllers are depicted in George et al, U.S. Pat. No. 3,637,092, wherein force feedback is presented at handle 45, and in Fick, U.S. Pat. No. 3,618,786, wherein a piston and cylinder assembly 25, 26 or 27, FIG. 1, provide "feel". In each of these patent disclosures the feedback of applied force is reflected as a resistance to movement at the hand-held controller.
Another type of controller encloses the operator's hand and provides signals at the hand to supply a "feel" that an action has taken place. Typical of this type is an Australian Patent No. 408,797 disclosing a bladder 47 which is located within a glove 11 that is worn by the operator. The bladder 47 is inflated to impart a feedback resistance force to the finger of the operator. A similar type system is disclosed in two Russian Pat. Nos. 234,762 and 234,763 wherein an openable case 3 has an inner surface that loosely embraces an operator's hand. In each one of these Russian patents, the case is movable to impart motion to an end effector. A handle is located within the opening in each case. In the '763 patent, the handle houses vibrators which cause a sensation on the palm of the operator's hand. In the two Russian patents, the operator's thumb and index finger fit within rings which drive a gripping mechanism, and also receive feedback signals at sensation-creating vibrators, or pushers, located at the tips of each ring.
In summary, then, it is known to provide control by a hand-held device, and to equip that device with some type of feedback resistance as an indication of a force applied at a controlled object. In other instances a vibration, such as the vibrators in the Russian patents, indicates that an action has taken place.
For sophisticated control over a robot end effector, it is a feature of this invention to provide a single tactile area with simultaneous feedback of both force and movement.